Nov 19 2012
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Thermal Properties
Other Designations
Applications
Introduction
Super alloys or high performance alloys are available in a variety of shapes and contain elements in different combinations to obtain a specific result. These alloys are of three types namely, iron-based, cobalt-based and nickel-based alloys. The nickel-based and cobalt-based super alloys are available as cast or wrought based alloys according to composition and application.
Super alloys have good oxidation and creep resistance and can be strengthened by precipitation hardening, solid-solution hardening and work hardening methods. They can also function under high mechanical stress and high temperatures and also in areas that require high surface stability.
The following datasheet provides an overview of super alloy 48.
Chemical Composition
The chemical composition of super alloy 48 is outlined in the following table.
|
Element |
Content (%) |
|
Iron, Fe |
49 |
|
Nickel, Ni |
48 |
|
Cobalt, Co |
1 |
|
Manganese, Mn |
0.80 |
|
Silicon, Si |
0.30 |
|
Chromium, Cr |
0.25 |
|
Aluminum, Al |
0.10 |
|
Carbon, C |
0.050 |
|
Phosphorous, P |
0.025 |
|
Sulfur, S |
0.025 |
Physical Properties
The following table shows the physical properties of super alloy 48.
|
Properties |
Metric |
Imperial |
|
Density |
8.20 g/cm³ |
0.296 lb/in³ |
|
Melting point |
1450°C |
2640°F |
Mechanical Properties
The mechanical properties of super alloy 48 are displayed in the following table.
|
Properties |
Metric |
Imperial |
|
Tensile strength (annealed prior to test) |
520 MPa |
75400 psi |
|
Yield strength (annealed prior to test, @strain 0.200%) |
260 MPa |
37700 psi |
|
Elongation at break (annealed prior to test) |
42% |
42% |
Thermal Properties
The thermal properties of super alloy 48 are given in the following table.
|
Properties |
Metric |
Imperial |
|
Thermal expansion co-efficient (@20-100°C/68-212 °F) |
8.50 µm/m°C |
4.72 µin/in°F |
|
Thermal conductivity |
16.7 W/mK |
116 BTU in/hr.ft².°F |
Other Designations
Equivalent materials to super alloy 48 are as follows:
-
ASTM A753 ALLOY 2
-
ASTM F30
-
MIL N-14411B Comp 3
Applications
Super alloy 48 is suitable for usage in industrial thermostats operating at temperatures up to 450°C (840°F). This alloy is also used for glass-to-metal seals in incandescent electric light bulbs and radio valves.